I didn't taste but it did smell a bit off and opted not to take any chances and dumped the batch. I am usually pretty good with sanitation and have gone more then 20 batches without any issues. One thing curious about though.......didn't notice any issues with the batch in primary.....fermentation was strong, had good krausen and not signs of infection........does that mean infection was introduced during the transfer to secondary or could it have been in primary and just didn't notice any signs?

Still say it wasn't infected. As someone else stated yeast and co2. As for the smell all you where smelling was co2 escaping. What a waste.....

I didn't taste but it did smell a bit off and opted not to take any chances and dumped the batch. I am usually pretty good with sanitation and have gone more then 20 batches without any issues. One thing curious about though.......didn't notice any issues with the batch in primary.....fermentation was strong, had good krausen and not signs of infection........does that mean infection was introduced during the transfer to secondary or could it have been in primary and just didn't notice any signs?

Nothing that can hurt you can survive in beer. You should always taste what seems like it might be an infected batch. It might be the best beer you ever made.